Access control systems are used, in general, for controlling the access of personnel to workplaces, e.g. through stamping apparatus, and/or to restricted areas. The access control system must grant and record the access to the authorized people and deny the access to unauthorized people.
The latest access control systems comprise a plurality of entrance controls, e.g. devices located at various access points in a firm or factory, being integrated into or associated with terminals as well as connected to one another and to a monitoring center by means of communication networks. Information relating to representative events of the access is exchanged over such communication networks. This information is used for checks involving comparisons with and alterations to information contained in databases implemented in computers being also associated with the communication networks. As said, there are also monitoring centers provided with terminals associated with the network in order to allow operators to monitor and check events related to access.
In order to ensure compliance with severe security standards, such access monitoring and control systems require that the detection and the control of the events happening in succession at the different access network nodes are performed as close to real time as possible. This real-time monitoring goal is however difficult to attain in a network architecture, especially without using highly specialized or dedicated hardware equipment and software management protocols.